Glutamine transferase occurs at a higher specific activity in the retina than in any other tissue and its appearance is known to correlate the maturation of the retina. The goal of the research project is to determine the purpose for an enzyme which at the moment has no known function. This investigation will involve a detailed study of glutamine transferase from the retina. The role of the enzyme in the eye will be examined from the standpoint of its potential for the inactivation of a possible retina neurotransmitter and/or modification of retinal membranes as has been suggested in preliminary studies in this laboratory.